No need to play for too long. Just got to -10k in 10~15 minutes.
All you gotta do is throw carrots to lead all the bunnies in the map to a single spot, then take a photo.
The more bunnies you have, the more points you get, so having a few (too many) dozens of bunnies in a single spot is a pretty quick way to get points. Rinse and repeat until you’re comfortable.
And I love abusing game mechanics to the point the game breaks, so seeing the points suddenly jump from around 15k to -10k was a pretty fun experience. =D